The invention concerns a chopper knife for a forage harvester, the knife including a cutting region including a leading side terminating at an outer cutting edge. U.S. Pat. No. 4,061,284, granted Dec.6, 1977, to Raisbeck et al. and U.S. Pat. No. 4,257,566, granted Mar. 24, 1981, to Lawrence, each disclose a chopper drum having a plurality of knife supports arranged in rows, each of which carries a generally plate-shaped chopper knife. Each of these chopper knives has a leading cutting region, while the rear region of the knife is used for fastening it to the knife support, for which purpose elongated slots and screws are provided. Sharpening of the cutting edges of the chopper knives of this chopper drum are ground, in that a grinding stone is guided over the cutting region while the chopper drum is rotating.
The problem with the known chopper knives is that undue power is required for their operation.